Lock-on heel lift



March 12, 1935. E, CHRISTENSEN 1,994,014

LOCK-0N HEEL LIFT Filed July 16, 1954 V 7 mm 57%;? 67777526121222. INVENTOR.

ATTORNEY Patented Mar. 12, 1935 Applicatidn t, 193 4,Sefla l Nor 7353555 My invention relates to :an -a-ttachable-detach able for the heel of a boot, shoe orthe that may be attached and detached without use of tools or implements of anycharacter and when attached will be locked against movement by reason'of .scuffing the heehasstriking the-.h l against a curb when stepping over it, and will not tend to become displaced if the wearer turns his heel over and stands on the side of it, or, it is believed, by any inadvertence whatever.

Another object is to provide a detachable lift for a heel that is inexpensive to make and which may be renewed when worn somewhat, to restore the appearance and level character of the heel, at;

The invention resides in the details of shape and the relationship of the interlocking surfaces as hereinafter more completely described in detail.

Drawings accompany and form a part of this specification in which,-

Fig. I is a longitudinal vertical section taken on the line I-Iof Fig. II and looking in the direction of the arrows showing part of a shoe in dotted outline with the heel and lift attached;

Fig. II is a projection of Fig. I; Fig. III is a plan view of the heel proper'when the shoe is reversed with the lift removed;

Fig. IV is a section on the line IV--IV of F I Fig. V is a plan view of the lift or'part which fits on to and looks with the heel proper, Fig. III; Fig. VI is an end elevation of Fig. V looking at the breast end of the heel lift; and 7 Figs. VII, VIII and IX are figures representing the successive stages of engagement of the lift with the heel proper as hereinafter explained.

In the drawing, 1 is the heel proper and 2 is the detachable wearing. portion or lift. 'Any suitable material may be used for these two elements but vulcanized rubber is preferred for both. The heel proper 1, to get the best results, should be made of a composition vulcanized somewhat harder than that used for the lift. The heel proper isprovided with a plurality of undercut grooves 3 having a definite length or limit stop 4 and the lift 2 is provided with corresponding interlocking undercut tongues 5, with rounded ends 6, which are undercut all the way around as shown so that their entire perimeter except the forward endgbecomesalocking surface with the heelprop er, ,6. engaging' with -theundercut portion 7 as shown i nEigs. IandIII. 1' i These .surfacesinterlock by entering asshown at .VII which is accomplished; by flexing 7th it at a. rim. lift is then'shoved ne r back figand E? are intimate contact .as shown in 'I'helift' then furtherfle'xed as shown at F2 in FigjIXfwhichalloWsthe interlocking tongue 9 to be engaged with the groove l0 and the lift and assume its level relationship to the heel as shown in the section at Fig. I.

The grooves 3 should preferably be spaced near the edges of the heel as shown and should-preferably be plural in number. The spacing should be arranged as shown in Fig. IV so that fastenings such as 11 tend to sustain the groove edges.

A lug'12 is shown made integral with the heel proper 1 and a corresponding recess 13 is shown engageable therewith. to resist blows or tendency to displace the lift sidewise with respect to the heel; and this combination of the interlocking tongue 9 and the groove 10 with the lug 12 and the recess 13 will be hereinafter referred to as interlocking angular surfaces. Y

Obviously the several interlocking surfaces delineated'and described couldbe reversed to some extent, for example placing the grooves 3 in the lift and the corresponding tongues 5 upon the heel, without departing from the principle of this invention,

It will be observed that the fastenings 11 ma be spaced in any convenient relationship around the edge of the heel proper and embedded therein, and that they will be completelyprotected from abrasion and to a large extent from moisture by the lift 2. Screws may be used instead of nails shown if preferred and will not become worn so that damaged slots might prevent their removal on occasion. They will also be so protected that they have scarcely any tendency to work-loose.

Numerous'structures have been heretofore proposed to accomplish the purpose and two-piece heels have heretofore been patented, though it is thought that their inherent incompleteness accounts for their making no commercial headway. A lift of this character to be successful must be locked to the heel proper nearits exposed edges and in particular it must be firmly lockedat its forward edge by substantial locking members since blows at that point are of frequent occurrence.

Having thus fully described my new invention in such a manner that its construction and advantages are fully made public, what I claim as new and desire to secure by Letters Patent, is,-

1. In a lock-on lift for a heel, a locking surface comprising a plurality of undercut tongues shorter than the lift and adapted to engage with matching undercut grooves in a heel, interlocking angular surfaces beyond the grooves and at substantially right angles thereto that are engageable with matching surfaces on the heel by flexing the lift into engaging position after engaging the tongues.

2. A lock-on heel for footwear comprisingin combination a heel member for permanent attachment, a lift lockable with the heelby underout tongues on one member and matching grooves on the other member that are Zengag'eable by retrograde movement of the lift with respect to the heel, the said tongues and grooves being shorter than the heel and lift and interlocking angular surfaces transverse to the grooves and rearwardly thereof that are engageable by flexing the lift into engagementwith the heel after fully engaging the tongues withthe grooves.

3. In a detachable heel for foot wear,a partial heel member, undercut grooves in said heel mem ber that are less than thelength of the heel, transverse angular locking devices integral with the heel positioned beyond the grooves, a lift member provided with matching tongues to fit the grooves by longitudinal retrograde movement with respect to the heel and matching transverse angular locking devices engageable by flexure into place after engaging the tongues and grooves 4. In a detachable lift for a heel, a lower wearing surface, the upper surface having undercut longitudinal locking devices adapted to endwise engagement with matching grooves on the lower face at the forwa'rd part of a heel member and transverse interlocking angular means for engagement with matching interlocking means, said first mentioned transverse means being engageable byfiexing into position of the rearward part of the upper surface of the lift.

5'5In aheel for footwear with detachable lift, a heelmemberadapted to be fastened to a shoe, longitudinal" undercut locking grooves on the forward part of the lower surface of the heel member adapted to endwise engagement with matching elevations on the lift by relative longitudinal movement, and transverse interlocking angular means on the other part of the lower surface of the heel member adapted for locking engagement with matching angular means on the upper surfaceofthe lift when the same is flexed into place; 1

' EMIL CHRISTENSEN. 

